/*
 * Copyright (C) 2015 The Android Open Source Project
 * Copyright LuckyJayce 2016
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */


package com.kwan.xframe.common.widget.indicator;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Rect;
import android.os.Build;
import android.os.Bundle;
import android.os.Parcel;
import android.os.Parcelable;
import androidx.annotation.NonNull;
import androidx.core.view.AccessibilityDelegateCompat;
import androidx.core.view.InputDeviceCompat;
import androidx.core.view.MotionEventCompat;
import androidx.core.view.NestedScrollingChild;
import androidx.core.view.NestedScrollingChildHelper;
import androidx.core.view.NestedScrollingParent;
import androidx.core.view.NestedScrollingParentHelper;
import androidx.core.view.ScrollingView;
import androidx.core.view.VelocityTrackerCompat;
import androidx.core.view.ViewCompat;
import androidx.core.view.accessibility.AccessibilityEventCompat;
import androidx.core.view.accessibility.AccessibilityNodeInfoCompat;
import androidx.core.view.accessibility.AccessibilityRecordCompat;
import androidx.core.widget.EdgeEffectCompat;
import androidx.core.widget.ScrollerCompat;
import android.util.AttributeSet;
import android.util.Log;
import android.util.TypedValue;
import android.view.FocusFinder;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.view.VelocityTracker;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.ViewGroup;
import android.view.ViewParent;
import android.view.accessibility.AccessibilityEvent;
import android.view.animation.AnimationUtils;
import android.widget.ScrollView;

import com.kwan.xframe.R;

import java.util.List;


/**
 * 作者：LuckyJayce
 * HVScrollView is just like {@link ScrollView}, but it supports acting
 * as both a nested scrolling parent and child on both new and old versions of Android.
 * can scroll horizontal and vertical
 * 能够水平和垂直滚动的 ScrollView，
 * 默认同时可以水平和垂直滚动
 * 当canScrollH 设置为false的时候就是一个垂直的的ScrollView
 * 当canScrollV 设置为false的时候就是一个水平的的ScrollView
 * 代码修改于v4的25.0.0版本的NestedScrollView，参考了RecyclerView的双向滚动的事件，参考了FrameLayoutd的onMeasure和ScrollView的HorizontalScrollView的onMeasure
 * 支持滑动末尾，ViewPager的页面切换
 */
public class HVScrollView extends ViewGroup implements NestedScrollingParent,
		NestedScrollingChild, ScrollingView {
	static final int ANIMATED_SCROLL_GAP = 250;

	static final float MAX_SCROLL_FACTOR = 0.5f;

	private static final String TAG = "NestedScrollView";
	private boolean mChildLayoutCenter;
	private int mInitialTouchY;
	private int mInitialTouchX;
//    private boolean mIsBeingDragged;

	public void setChildLayoutCenter(boolean childLayoutCenter) {
		if (mChildLayoutCenter != childLayoutCenter) {
			this.mChildLayoutCenter = childLayoutCenter;
			requestLayout();
		}
	}

	/**
	 * Interface definition for a callback to be invoked when the scroll
	 * X or Y positions of a view change.
	 *
	 * This version of the interface works on all versions of Android, back to API v4.
	 *
	 * @see #setOnScrollChangeListener(OnScrollChangeListener)
	 */
	public interface OnScrollChangeListener {
		/**
		 * Called when the scroll position of a view changes.
		 *
		 * @param v          The view whose scroll position has changed.
		 * @param scrollX    Current horizontal scroll origin.
		 * @param scrollY    Current vertical scroll origin.
		 * @param oldScrollX Previous horizontal scroll origin.
		 * @param oldScrollY Previous vertical scroll origin.
		 */
		void onScrollChange(HVScrollView v, int scrollX, int scrollY,
							int oldScrollX, int oldScrollY);
	}

	private long mLastScroll;

	private final Rect mTempRect = new Rect();
	private ScrollerCompat mScroller;
	private EdgeEffectCompat mEdgeGlowTop;
	private EdgeEffectCompat mEdgeGlowBottom;
	private EdgeEffectCompat mEdgeGlowLeft;
	private EdgeEffectCompat mEdgeGlowRight;

	/**
	 * Position of the last motion event.
	 */
	private int mLastMotionY;

	private int mLastMotionX;

	/**
	 * True when the layout has changed but the traversal has not come through yet.
	 * Ideally the view hierarchy would keep track of this for us.
	 */
	private boolean mIsLayoutDirty = true;
	private boolean mIsLaidOut = false;

	/**
	 * The child to give focus to in the event that a child has requested focus while the
	 * layout is dirty. This prevents the scroll from being wrong if the child has not been
	 * laid out before requesting focus.
	 */
	private View mChildToScrollTo = null;

//    /**
//     * True if the user is currently dragging this ScrollView around. This is
//     * not the same as 'is being flinged', which can be checked by
//     * mScroller.isFinished() (flinging begins when the user lifts his finger).
//     */
//    private boolean mIsBeingDragged = false;

	/**
	 * The RecyclerView is not currently scrolling.
	 */
	public static final int SCROLL_STATE_IDLE = 0;

	/**
	 * The RecyclerView is currently being dragged by outside input such as user touch input.
	 */
	public static final int SCROLL_STATE_DRAGGING = 1;

	/**
	 * The RecyclerView is currently animating to a final position while not under
	 * outside control.
	 */
	public static final int SCROLL_STATE_SETTLING = 2;

	// Touch/scrolling handling

	private int mScrollState = SCROLL_STATE_IDLE;

	/**
	 * Determines speed during touch scrolling
	 */
	private VelocityTracker mVelocityTracker;

	/**
	 * Whether arrow scrolling is animated.
	 */
	private boolean mSmoothScrollingEnabled = true;

	private int mTouchSlop;
	private int mMinimumVelocity;
	private int mMaximumVelocity;

	/**
	 * ID of the active pointer. This is used to retain consistency during
	 * drags/flings if multiple pointers are used.
	 */
	private int mActivePointerId = INVALID_POINTER;

	/**
	 * Used during scrolling to retrieve the new offset within the window.
	 */
	private final int[] mScrollOffset = new int[2];
	private final int[] mScrollConsumed = new int[2];
	private int mNestedYOffset;
	private int mNestedXOffset;

	/**
	 * Sentinel value for no current active pointer.
	 * Used by {@link #mActivePointerId}.
	 */
	private static final int INVALID_POINTER = -1;

	private SavedState mSavedState;

	private static final AccessibilityDelegate ACCESSIBILITY_DELEGATE = new AccessibilityDelegate();

	private boolean mFillViewportH;
	private boolean mFillViewportV;
	private final NestedScrollingParentHelper mParentHelper;
	private final NestedScrollingChildHelper mChildHelper;

	private float mVerticalScrollFactor;

	private OnScrollChangeListener mOnScrollChangeListener;

	public HVScrollView(Context context) {
		this(context, null);
	}

	public HVScrollView(Context context, AttributeSet attrs) {
		this(context, attrs, 0);
	}

	public static final int SCROLL_ORIENTATION_NONE = 0;
	public static final int SCROLL_ORIENTATION_HORIZONTAL = 1;
	public static final int SCROLL_ORIENTATION_VERTICAL = 2;
	public static final int SCROLL_ORIENTATION_BOTH = 3;
	private int mScrollOrientation;

	public void setScrollOrientation(int scrollOrientation) {
		this.mScrollOrientation = scrollOrientation;
		requestLayout();
	}

	public int getScrollOrientation() {
		return mScrollOrientation;
	}

	public HVScrollView(Context context, AttributeSet attrs, int defStyleAttr) {
		super(context, attrs, defStyleAttr);
		initScrollView();

		final TypedArray a = context.obtainStyledAttributes(
				attrs, R.styleable.HVScrollView, defStyleAttr, 0);

		mChildLayoutCenter = a.getBoolean(R.styleable.HVScrollView_childLayoutCenter, false);
		mFillViewportH = a.getBoolean(R.styleable.HVScrollView_fillViewportH, false);
		mFillViewportV = a.getBoolean(R.styleable.HVScrollView_fillViewportV, false);
		mScrollOrientation = a.getInt(R.styleable.HVScrollView_scrollOrientation, SCROLL_ORIENTATION_BOTH);

		a.recycle();

		mParentHelper = new NestedScrollingParentHelper(this);
		mChildHelper = new NestedScrollingChildHelper(this);

		// ...because why else would you be using this widget?
		setNestedScrollingEnabled(true);

		ViewCompat.setAccessibilityDelegate(this, ACCESSIBILITY_DELEGATE);
	}

	// NestedScrollingChild

	@Override
	public void setNestedScrollingEnabled(boolean enabled) {
		mChildHelper.setNestedScrollingEnabled(enabled);
	}

	@Override
	public boolean isNestedScrollingEnabled() {
		return mChildHelper.isNestedScrollingEnabled();
	}

	@Override
	public boolean startNestedScroll(int axes) {
		return mChildHelper.startNestedScroll(axes);
	}

	@Override
	public void stopNestedScroll() {
		mChildHelper.stopNestedScroll();
	}

	@Override
	public boolean hasNestedScrollingParent() {
		return mChildHelper.hasNestedScrollingParent();
	}

	@Override
	public boolean dispatchNestedScroll(int dxConsumed, int dyConsumed, int dxUnconsumed,
										int dyUnconsumed, int[] offsetInWindow) {
		return mChildHelper.dispatchNestedScroll(dxConsumed, dyConsumed, dxUnconsumed, dyUnconsumed,
				offsetInWindow);
	}

	@Override
	public boolean dispatchNestedPreScroll(int dx, int dy, int[] consumed, int[] offsetInWindow) {
		return mChildHelper.dispatchNestedPreScroll(dx, dy, consumed, offsetInWindow);
	}

	@Override
	public boolean dispatchNestedFling(float velocityX, float velocityY, boolean consumed) {
		return mChildHelper.dispatchNestedFling(velocityX, velocityY, consumed);
	}

	@Override
	public boolean dispatchNestedPreFling(float velocityX, float velocityY) {
		return mChildHelper.dispatchNestedPreFling(velocityX, velocityY);
	}

	// NestedScrollingParent

	@Override
	public boolean onStartNestedScroll(@NonNull View child, @NonNull View target, int nestedScrollAxes) {
		return ((nestedScrollAxes & ViewCompat.SCROLL_AXIS_VERTICAL) != 0 && canScrollVertically()) || ((nestedScrollAxes & ViewCompat.SCROLL_AXIS_HORIZONTAL) != 0 && canScrollHorizontally());
	}

	@Override
	public void onNestedScrollAccepted(@NonNull View child, @NonNull View target, int nestedScrollAxes) {
		mParentHelper.onNestedScrollAccepted(child, target, nestedScrollAxes);
		int axes = ViewCompat.SCROLL_AXIS_NONE;
		axes = canScrollHorizontally() ? axes | ViewCompat.SCROLL_AXIS_HORIZONTAL : axes;
		axes = canScrollVertically() ? axes | ViewCompat.SCROLL_AXIS_VERTICAL : axes;
		startNestedScroll(axes);
	}

	@Override
	public void onStopNestedScroll(@NonNull View target) {
		mParentHelper.onStopNestedScroll(target);
		stopNestedScroll();
	}

	public boolean canScrollHorizontally() {
		return (mScrollOrientation & SCROLL_ORIENTATION_HORIZONTAL) == SCROLL_ORIENTATION_HORIZONTAL;
	}

	public boolean canScrollVertically() {
		return (mScrollOrientation & SCROLL_ORIENTATION_VERTICAL) == SCROLL_ORIENTATION_VERTICAL;
	}


	@Override
	public void onNestedScroll(@NonNull View target, int dxConsumed, int dyConsumed, int dxUnconsumed,
							   int dyUnconsumed) {
		final int oldScrollY = getScrollY();
		final int oldScrollX = getScrollX();
		scrollBy(canScrollHorizontally() ? dxUnconsumed : 0, canScrollVertically() ? dyUnconsumed : 0);
		final int myConsumedY = getScrollY() - oldScrollY;
		final int myConsumedX = getScrollX() - oldScrollX;
		final int myUnconsumedY = dyUnconsumed - myConsumedY;
		final int myUnconsumedX = dxUnconsumed - myConsumedX;
		dispatchNestedScroll(myConsumedX, myConsumedY, myUnconsumedX, myUnconsumedY, null);
	}

	@Override
	public void onNestedPreScroll(@NonNull View target, int dx, int dy, @NonNull int[] consumed) {
		dispatchNestedPreScroll(dx, dy, consumed, null);
	}

	@Override
	public boolean onNestedFling(@NonNull View target, float velocityX, float velocityY, boolean consumed) {
		if (!consumed) {
			fling((int) velocityX, (int) velocityY);
			return true;
		}
		return false;
	}

	@Override
	public boolean onNestedPreFling(@NonNull View target, float velocityX, float velocityY) {
		return dispatchNestedPreFling(velocityX, velocityY);
	}

	@Override
	public int getNestedScrollAxes() {
		return mParentHelper.getNestedScrollAxes();
	}

	// ScrollView import

	public boolean shouldDelayChildPressedState() {
		return true;
	}

	@Override
	protected float getLeftFadingEdgeStrength() {
		if (getChildCount() == 0 || !canScrollHorizontally()) {
			return 0.0f;
		}

		final int length = getHorizontalFadingEdgeLength();
		final int scrollX = getScrollX();
		if (scrollX < length) {
			return scrollX / (float) length;
		}
		return 1.0f;
	}

	@Override
	protected float getTopFadingEdgeStrength() {
		if (getChildCount() == 0 || !canScrollVertically()) {
			return 0.0f;
		}

		final int length = getVerticalFadingEdgeLength();
		final int scrollY = getScrollY();
		if (scrollY < length) {
			return scrollY / (float) length;
		}
		return 1.0f;
	}

	@Override
	protected float getBottomFadingEdgeStrength() {
		if (getChildCount() == 0 || !canScrollVertically()) {
			return 0.0f;
		}

		final int length = getVerticalFadingEdgeLength();
		final int bottomEdge = getHeight() - getPaddingBottom();
		final int span = getChildAt(0).getBottom() - getScrollY() - bottomEdge;
		if (span < length) {
			return span / (float) length;
		}

		return 1.0f;
	}

	@Override
	protected float getRightFadingEdgeStrength() {
		if (getChildCount() == 0 || !canScrollHorizontally()) {
			return 0.0f;
		}

		final int length = getHorizontalFadingEdgeLength();
		final int rightEdge = getWidth() - getPaddingRight();
		final int span = getChildAt(0).getRight() - getScrollX() - rightEdge;
		if (span < length) {
			return span / (float) length;
		}

		return 1.0f;
	}

	/**
	 * @return The maximum amount this scroll view will scroll in response to
	 * an arrow event.
	 */
	public int getMaxScrollAmountY() {
		return (int) (MAX_SCROLL_FACTOR * getHeight());
	}

	public int getMaxScrollAmountX() {
		return (int) (MAX_SCROLL_FACTOR * getWidth());
	}

	private void initScrollView() {
		mScroller = ScrollerCompat.create(getContext(), null);
		setFocusable(true);
		setDescendantFocusability(FOCUS_AFTER_DESCENDANTS);
		setWillNotDraw(false);
		final ViewConfiguration configuration = ViewConfiguration.get(getContext());
		mTouchSlop = configuration.getScaledTouchSlop();
		mMinimumVelocity = configuration.getScaledMinimumFlingVelocity();
		mMaximumVelocity = configuration.getScaledMaximumFlingVelocity();
	}

	@Override
	public void addView(View child) {
		if (getChildCount() > 0) {
			throw new IllegalStateException("ScrollView can host only one direct child");
		}

		super.addView(child);
	}

	@Override
	public void addView(View child, int index) {
		if (getChildCount() > 0) {
			throw new IllegalStateException("ScrollView can host only one direct child");
		}

		super.addView(child, index);
	}

	@Override
	public void addView(View child, LayoutParams params) {
		if (getChildCount() > 0) {
			throw new IllegalStateException("ScrollView can host only one direct child");
		}

		super.addView(child, params);
	}

	@Override
	public void addView(View child, int index, LayoutParams params) {
		if (getChildCount() > 0) {
			throw new IllegalStateException("ScrollView can host only one direct child");
		}

		super.addView(child, index, params);
	}

	/**
	 * Register a callback to be invoked when the scroll X or Y positions of
	 * this view change.
	 * This version of the method works on all versions of Android, back to API v4.
	 *
	 * @param l The listener to notify when the scroll X or Y position changes.
	 * @see View#getScrollX()
	 * @see View#getScrollY()
	 */
	public void setOnScrollChangeListener(OnScrollChangeListener l) {
		mOnScrollChangeListener = l;
	}

	/**
	 * @return Returns true this ScrollView can be scrolled
	 */
	private boolean canScroll() {
		View child = getChildAt(0);
		if (child != null) {
			int childHeight = child.getHeight();
			int childWidth = child.getWidth();
			boolean canY = getHeight() < childHeight + getPaddingTop() + getPaddingBottom();
			canY |= canScrollVertically();
			boolean canX = getWidth() < childWidth + getPaddingLeft() + getPaddingRight();
			canX |= canScrollHorizontally();
			return canX || canY;
		}
		return false;
	}

	/**
	 * @return Whether arrow scrolling will animate its transition.
	 */
	public boolean isSmoothScrollingEnabled() {
		return mSmoothScrollingEnabled;
	}

	/**
	 * Set whether arrow scrolling will animate its transition.
	 *
	 * @param smoothScrollingEnabled whether arrow scrolling will animate its transition
	 */
	public void setSmoothScrollingEnabled(boolean smoothScrollingEnabled) {
		mSmoothScrollingEnabled = smoothScrollingEnabled;
	}

	@Override
	protected void onScrollChanged(int l, int t, int oldl, int oldt) {
		super.onScrollChanged(l, t, oldl, oldt);

		if (mOnScrollChangeListener != null) {
			mOnScrollChangeListener.onScrollChange(this, l, t, oldl, oldt);
		}
	}

	@Override
	public boolean dispatchKeyEvent(KeyEvent event) {
		// Let the focused view and/or our descendants get the key first
		return super.dispatchKeyEvent(event) || executeKeyEvent(event);
	}

	/**
	 * You can call this function yourself to have the scroll view perform
	 * scrolling from a key event, just as if the event had been dispatched to
	 * it by the view hierarchy.
	 *
	 * @param event The key event to execute.
	 * @return Return true if the event was handled, else false.
	 */
	public boolean executeKeyEvent(KeyEvent event) {
		mTempRect.setEmpty();

		if (!canScroll()) {
			if (isFocused() && event.getKeyCode() != KeyEvent.KEYCODE_BACK) {
				View currentFocused = findFocus();
				if (currentFocused == this) currentFocused = null;
				View nextFocused = FocusFinder.getInstance().findNextFocus(this,
						currentFocused, View.FOCUS_DOWN);
				return nextFocused != null
						&& nextFocused != this
						&& nextFocused.requestFocus(View.FOCUS_DOWN);
			}
			return false;
		}

		boolean handled = false;
		if (event.getAction() == KeyEvent.ACTION_DOWN) {
			switch (event.getKeyCode()) {
				case KeyEvent.KEYCODE_DPAD_UP:
					if (canScrollVertically()) {
						if (!event.isAltPressed()) {
							handled = arrowScrollVertically(View.FOCUS_UP);
						} else {
							handled = fullScrollVertically(View.FOCUS_UP);
						}
					}
					break;
				case KeyEvent.KEYCODE_DPAD_DOWN:
					if (canScrollVertically()) {
						if (!event.isAltPressed()) {
							handled = arrowScrollVertically(View.FOCUS_DOWN);
						} else {
							handled = fullScrollVertically(View.FOCUS_DOWN);
						}
					}
					break;
				case KeyEvent.KEYCODE_DPAD_LEFT:
					if (canScrollHorizontally()) {
						if (!event.isAltPressed()) {
							handled = arrowScrollHorizontally(View.FOCUS_LEFT);
						} else {
							handled = fullScrollHorizontally(View.FOCUS_LEFT);
						}
					}
					break;
				case KeyEvent.KEYCODE_DPAD_RIGHT:
					if (canScrollHorizontally()) {
						if (!event.isAltPressed()) {
							handled = arrowScrollHorizontally(View.FOCUS_DOWN);
						} else {
							handled = fullScrollHorizontally(View.FOCUS_DOWN);
						}
					}
					break;
				case KeyEvent.KEYCODE_SPACE:
					if (canScrollHorizontally()) {
						pageScrollHorizontally(event.isShiftPressed() ? View.FOCUS_UP : View.FOCUS_DOWN);
					} else if (canScrollVertically()) {
						pageScrollVertically(event.isShiftPressed() ? View.FOCUS_UP : View.FOCUS_DOWN);
					}
					break;
			}
		}

		return handled;
	}

	private boolean inChild(int x, int y) {
		if (getChildCount() > 0) {
			final int scrollY = getScrollY();
			final View child = getChildAt(0);
			return !(y < child.getTop() - scrollY
					|| y >= child.getBottom() - scrollY
					|| x < child.getLeft()
					|| x >= child.getRight());
		}
		return false;
	}

	private void initOrResetVelocityTracker() {
		if (mVelocityTracker == null) {
			mVelocityTracker = VelocityTracker.obtain();
		} else {
			mVelocityTracker.clear();
		}
	}

	private void initVelocityTrackerIfNotExists() {
		if (mVelocityTracker == null) {
			mVelocityTracker = VelocityTracker.obtain();
		}
	}

	private void recycleVelocityTracker() {
		if (mVelocityTracker != null) {
			mVelocityTracker.recycle();
			mVelocityTracker = null;
		}
	}

	@Override
	public void requestDisallowInterceptTouchEvent(boolean disallowIntercept) {
		if (disallowIntercept) {
			recycleVelocityTracker();
		}
		super.requestDisallowInterceptTouchEvent(disallowIntercept);
	}

	private void setScrollState(int state) {
		if (state == mScrollState) {
			return;
		}
		boolean DEBUG = false;
		if (DEBUG) {
			Log.d(TAG, "setting scroll state to " + state + " from " + mScrollState,
					new Exception());
		}
		mScrollState = state;
		if (state != SCROLL_STATE_SETTLING) {
//            stopScrollersInternal();
		}
//        dispatchOnScrollStateChanged(state);
	}

	private void cancelTouch() {
		resetTouch();
		setScrollState(SCROLL_STATE_IDLE);
	}

	private void resetTouch() {
		recycleVelocityTracker();
		stopNestedScroll();
		releaseGlows();
	}

	private void releaseGlows() {
		boolean needsInvalidate = false;
		if (mEdgeGlowLeft != null) needsInvalidate = mEdgeGlowLeft.onRelease();
		if (mEdgeGlowTop != null) needsInvalidate |= mEdgeGlowTop.onRelease();
		if (mEdgeGlowRight != null) needsInvalidate |= mEdgeGlowRight.onRelease();
		if (mEdgeGlowBottom != null) needsInvalidate |= mEdgeGlowBottom.onRelease();
		if (needsInvalidate) {
			ViewCompat.postInvalidateOnAnimation(this);
		}
	}

	@Override
	public boolean onInterceptTouchEvent(MotionEvent ev) {
        /*
         * This method JUST determines whether we want to intercept the motion.
         * If we return true, onMotionEvent will be called and we do the actual
         * scrolling there.
         */

        /*
        * Shortcut the most recurring case: the user is in the dragging
        * state and he is moving his finger.  We want to intercept this
        * motion.
        */


		final int action = ev.getAction();
//        if ((action == MotionEvent.ACTION_MOVE) && (mIsBeingDragged)) {
//            return true;
//        }

		if (action == MotionEvent.ACTION_MOVE && mScrollState == SCROLL_STATE_DRAGGING) {
			return true;
		}

		setScrollState(SCROLL_STATE_IDLE);

		final boolean canScrollHorizontally = canScrollHorizontally();
		final boolean canScrollVertically = canScrollVertically();

		switch (action & MotionEventCompat.ACTION_MASK) {
			case MotionEvent.ACTION_MOVE: {
                /*
                 * mIsBeingDragged == false, otherwise the shortcut would have caught it. Check
                 * whether the user has moved far enough from his original down touch.
                 */

                /*
                * Locally do absolute value. mLastMotionY is set to the y value
                * of the down event.
                */
				final int activePointerId = mActivePointerId;
				if (activePointerId == INVALID_POINTER) {
					// If we don't have a valid id, the touch down wasn't on content.
					break;
				}

				final int pointerIndex = MotionEventCompat.findPointerIndex(ev, activePointerId);
				if (pointerIndex == -1) {
					Log.e(TAG, "Invalid pointerId=" + activePointerId
							+ " in onInterceptTouchEvent");
					break;
				}

				final int y = (int) MotionEventCompat.getY(ev, pointerIndex);
				final int x = (int) MotionEventCompat.getX(ev, pointerIndex);
				if (mScrollState != SCROLL_STATE_DRAGGING) {
					final int dx = x - mInitialTouchX;
					final int dy = y - mInitialTouchY;
					boolean startScroll = false;
					if (canScrollHorizontally && Math.abs(dx) > mTouchSlop) {
						mLastMotionX = mInitialTouchX + mTouchSlop * (dx < 0 ? -1 : 1);
						startScroll = true;
					}
					if (canScrollVertically && Math.abs(dy) > mTouchSlop) {
						mLastMotionY = mInitialTouchY + mTouchSlop * (dy < 0 ? -1 : 1);
						startScroll = true;
					}
					initVelocityTrackerIfNotExists();
					mVelocityTracker.addMovement(ev);
					mNestedYOffset = 0;
					if (startScroll) {
//                        mIsBeingDragged = true;
						setScrollState(SCROLL_STATE_DRAGGING);
					}
				}
				break;
			}

			case MotionEvent.ACTION_DOWN: {
				final int y = (int) ev.getY();
				final int x = (int) ev.getX();
				if (!inChild(x, y)) {
					setScrollState(SCROLL_STATE_IDLE);
					recycleVelocityTracker();
					break;
				}


                /*
                 * Remember location of down touch.
                 * ACTION_DOWN always refers to pointer index 0.
                 */
				mLastMotionY = y;
				mLastMotionX = x;
				mInitialTouchY = mLastMotionY;
				mInitialTouchX = mLastMotionX;

				mActivePointerId = MotionEventCompat.getPointerId(ev, 0);

				initOrResetVelocityTracker();
				mVelocityTracker.addMovement(ev);
                /*
                 * If being flinged and user touches the screen, initiate drag;
                 * otherwise don't. mScroller.isFinished should be false when
                 * being flinged. We need to call computeScrollOffset() first so that
                 * isFinished() is correct.
                */
				mScroller.computeScrollOffset();
//                mIsBeingDragged = !mScroller.isFinished();

				if (mScrollState == SCROLL_STATE_SETTLING) {
					getParent().requestDisallowInterceptTouchEvent(true);
					setScrollState(SCROLL_STATE_DRAGGING);
				}
				int nestedScrollAxis = ViewCompat.SCROLL_AXIS_NONE;
				if (canScrollHorizontally) {
					nestedScrollAxis |= ViewCompat.SCROLL_AXIS_HORIZONTAL;
				}
				if (canScrollVertically) {
					nestedScrollAxis |= ViewCompat.SCROLL_AXIS_VERTICAL;
				}
				startNestedScroll(nestedScrollAxis);
				break;
			}

			case MotionEvent.ACTION_CANCEL:
//                mIsBeingDragged = false;
				cancelTouch();
				break;
			case MotionEvent.ACTION_UP:
                /* Release the drag */
//                mIsBeingDragged = false;
//                mActivePointerId = INVALID_POINTER;
				recycleVelocityTracker();
//                if (mScroller.springBack(getScrollX(), getScrollY(), 0, getScrollRangeX(), 0, getScrollRangeY())) {
//                    ViewCompat.postInvalidateOnAnimation(this);
//                }
				stopNestedScroll();
				break;
			case MotionEvent.ACTION_POINTER_UP:
				onSecondaryPointerUp(ev);
				break;
		}

        /*
        * The only time we want to intercept motion events is if we are in the
        * drag mode.
        */
		return false;
	}

	@Override
	public boolean onTouchEvent(MotionEvent ev) {

		initVelocityTrackerIfNotExists();

		MotionEvent vtev = MotionEvent.obtain(ev);

		final boolean canScrollHorizontally = canScrollHorizontally();
		final boolean canScrollVertically = canScrollVertically();

		final int actionMasked = ev.getActionMasked();

		if (actionMasked == MotionEvent.ACTION_DOWN) {
			mNestedYOffset = 0;
			mNestedXOffset = 0;
		}
		vtev.offsetLocation(mNestedXOffset, mNestedYOffset);

		switch (actionMasked) {
			case MotionEvent.ACTION_DOWN: {

                /*
                 * If being flinged and user touches, stop the fling. isFinished
                 * will be false if being flinged.
                 */
				if (!mScroller.isFinished()) {
					mScroller.abortAnimation();
				}

				// Remember where the motion event started
				mInitialTouchX = mLastMotionY = (int) ev.getY();
				mInitialTouchY = mLastMotionX = (int) ev.getX();
				mActivePointerId = MotionEventCompat.getPointerId(ev, 0);

				int nestedScrollAxis = ViewCompat.SCROLL_AXIS_NONE;
				if (canScrollHorizontally) {
					nestedScrollAxis |= ViewCompat.SCROLL_AXIS_HORIZONTAL;
				}
				if (canScrollVertically) {
					nestedScrollAxis |= ViewCompat.SCROLL_AXIS_VERTICAL;
				}
				startNestedScroll(nestedScrollAxis);
				break;
			}
			case MotionEvent.ACTION_MOVE:
				final int activePointerIndex = MotionEventCompat.findPointerIndex(ev,
						mActivePointerId);
				if (activePointerIndex == -1) {
					Log.e(TAG, "Invalid pointerId=" + mActivePointerId + " in onTouchEvent");
					return false;
				}

				final int y = (int) MotionEventCompat.getY(ev, activePointerIndex);
				final int x = (int) MotionEventCompat.getX(ev, activePointerIndex);
				int dy = mLastMotionY - y;
				int dx = mLastMotionX - x;
				if (dispatchNestedPreScroll(dx, dy, mScrollConsumed, mScrollOffset)) {
					dy -= mScrollConsumed[1];
					dx -= mScrollConsumed[0];
					vtev.offsetLocation(mScrollOffset[0], mScrollOffset[1]);
					mNestedYOffset += mScrollOffset[1];
					mNestedXOffset += mScrollOffset[0];
				}

				if (mScrollState != SCROLL_STATE_DRAGGING) {
					boolean startScroll = false;
					if (canScrollHorizontally && Math.abs(dx) > mTouchSlop) {
						if (dx > 0) {
							dx -= mTouchSlop;
						} else {
							dx += mTouchSlop;
						}
						startScroll = true;
					}
					if (canScrollVertically && Math.abs(dy) > mTouchSlop) {
						if (dy > 0) {
							dy -= mTouchSlop;
						} else {
							dy += mTouchSlop;
						}
						startScroll = true;
					}
					if (startScroll) {
						setScrollState(SCROLL_STATE_DRAGGING);
					}
				}

				if (mScrollState == SCROLL_STATE_DRAGGING) {
					// Scroll to follow the motion event
					mLastMotionY = y - mScrollOffset[1];
					mLastMotionX = x - mScrollOffset[0];

					final int oldY = getScrollY();
					final int oldX = getScrollX();
					final int rangeY = getScrollRangeY();
					final int rangeX = getScrollRangeX();
					final int overscrollMode = ViewCompat.getOverScrollMode(this);
					boolean canOverscrollY = overscrollMode == ViewCompat.OVER_SCROLL_ALWAYS ||
							(overscrollMode == ViewCompat.OVER_SCROLL_IF_CONTENT_SCROLLS &&
									rangeY > 0);
					boolean canOverscrollX = overscrollMode == ViewCompat.OVER_SCROLL_ALWAYS ||
							(overscrollMode == ViewCompat.OVER_SCROLL_IF_CONTENT_SCROLLS &&
									rangeX > 0);
					boolean canOverscroll = (canOverscrollY && canScrollVertically()) || (canOverscrollX && canScrollHorizontally());

//                    final ViewParent parent = getParent();
//                    if (parent != null) {
//                        parent.requestDisallowInterceptTouchEvent(true);
//                    }

					// Calling overScrollByCompat will call onOverScrolled, which
					// calls onScrollChanged if applicable.
					if (overScrollByCompat(dx, dy, getScrollX(), getScrollY(), rangeX, rangeY, 0, 0, true)) {
						// Break our velocity if we hit a scroll barrier.
//                        mVelocityTracker.clear();
						if (mChildHelper.hasNestedScrollingParent()) {
							getParent().requestDisallowInterceptTouchEvent(true);
						}
					}

					final int scrolledDeltaY = getScrollY() - oldY;
					final int scrolledDeltaX = getScrollX() - oldX;
					final int unconsumedY = dy - scrolledDeltaY;
					final int unconsumedX = dx - scrolledDeltaX;
					if (dispatchNestedScroll(scrolledDeltaX, scrolledDeltaY, unconsumedX, unconsumedY, mScrollOffset)) {
						mLastMotionY -= mScrollOffset[1];
						mLastMotionX -= mScrollOffset[0];
						vtev.offsetLocation(mScrollOffset[0], mScrollOffset[1]);
						mNestedYOffset += mScrollOffset[1];
						mNestedXOffset += mScrollOffset[0];
					} else if (canOverscroll) {
						ensureGlows();
						final int pulledToY = oldY + dy;
						final int pulledToX = oldX + dx;
						if (canScrollVertically()) {
							if (pulledToY < 0) {
								mEdgeGlowTop.onPull((float) dy / getHeight(), MotionEventCompat.getX(ev, activePointerIndex) / getWidth());
								if (!mEdgeGlowBottom.isFinished()) {
									mEdgeGlowBottom.onRelease();
								}
							} else if (pulledToY > rangeY) {
								mEdgeGlowBottom.onPull((float) dy / getHeight(), 1.f - MotionEventCompat.getX(ev, activePointerIndex) / getWidth());
								if (!mEdgeGlowTop.isFinished()) {
									mEdgeGlowTop.onRelease();
								}
							}
						}
						if (canScrollHorizontally()) {
							if (pulledToX < 0) {
								mEdgeGlowLeft.onPull((float) dx / getWidth(), MotionEventCompat.getX(ev, activePointerIndex) / getHeight());
								if (!mEdgeGlowLeft.isFinished()) {
									mEdgeGlowLeft.onRelease();
								}
							} else if (pulledToX > rangeX) {
								mEdgeGlowRight.onPull((float) dx / getWidth(), 1.f - MotionEventCompat.getX(ev, activePointerIndex) / getHeight());
								if (!mEdgeGlowRight.isFinished()) {
									mEdgeGlowRight.onRelease();
								}
							}
						}
						if (mEdgeGlowTop != null && (!mEdgeGlowTop.isFinished() || !mEdgeGlowBottom.isFinished() || !mEdgeGlowLeft.isFinished() || !mEdgeGlowRight.isFinished())) {
							ViewCompat.postInvalidateOnAnimation(this);
						}
					}
				}
				break;
			case MotionEvent.ACTION_UP:
				final VelocityTracker velocityTracker = mVelocityTracker;
				velocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);

				final float xvel = canScrollHorizontally ?
						-VelocityTrackerCompat.getXVelocity(mVelocityTracker, mActivePointerId) : 0;
				final float yvel = canScrollVertically ?
						-VelocityTrackerCompat.getYVelocity(mVelocityTracker, mActivePointerId) : 0;

				if (fling((int) xvel, (int) yvel)) {
					setScrollState(SCROLL_STATE_IDLE);
				} else if (mScroller.springBack(getScrollX(), getScrollY(), 0, getScrollRangeX(), 0, getScrollRangeY())) {
					ViewCompat.postInvalidateOnAnimation(this);
				}
				mActivePointerId = INVALID_POINTER;
				resetTouch();
				break;
			case MotionEvent.ACTION_CANCEL:
				if (mScrollState == SCROLL_STATE_DRAGGING) {
					if (mScroller.springBack(getScrollX(), getScrollY(), 0, getScrollRangeX(), 0, getScrollRangeY())) {
						ViewCompat.postInvalidateOnAnimation(this);
					}
				}
				mActivePointerId = INVALID_POINTER;
				cancelTouch();
				break;
			case MotionEventCompat.ACTION_POINTER_DOWN: {
				final int index = MotionEventCompat.getActionIndex(ev);
				mInitialTouchX = mLastMotionY = (int) MotionEventCompat.getY(ev, index);
				mInitialTouchX = mLastMotionX = (int) MotionEventCompat.getX(ev, index);
				mActivePointerId = MotionEventCompat.getPointerId(ev, index);
				break;
			}
			case MotionEventCompat.ACTION_POINTER_UP:
				onSecondaryPointerUp(ev);
				break;
		}

		if (mVelocityTracker != null) {
			mVelocityTracker.addMovement(vtev);
		}
		vtev.recycle();
		return true;
	}

	private void onSecondaryPointerUp(MotionEvent ev) {
		final int pointerIndex = (ev.getAction() & MotionEventCompat.ACTION_POINTER_INDEX_MASK) >>
				MotionEventCompat.ACTION_POINTER_INDEX_SHIFT;
		final int pointerId = MotionEventCompat.getPointerId(ev, pointerIndex);
		if (pointerId == mActivePointerId) {
			// This was our active pointer going up. Choose a new
			// active pointer and adjust accordingly.
			// TODO: Make this decision more intelligent.
			final int newPointerIndex = pointerIndex == 0 ? 1 : 0;
			mInitialTouchX = mLastMotionY = (int) MotionEventCompat.getY(ev, newPointerIndex);
			mInitialTouchY = mLastMotionX = (int) MotionEventCompat.getX(ev, newPointerIndex);
			mActivePointerId = MotionEventCompat.getPointerId(ev, newPointerIndex);
			if (mVelocityTracker != null) {
				mVelocityTracker.clear();
			}
		}
	}

	public boolean onGenericMotionEvent(MotionEvent event) {
		if ((MotionEventCompat.getSource(event) & InputDeviceCompat.SOURCE_CLASS_POINTER) != 0) {
			switch (event.getAction()) {
				case MotionEventCompat.ACTION_SCROLL: {
					final float vscroll = MotionEventCompat.getAxisValue(event, MotionEventCompat.AXIS_VSCROLL);
					final float hscroll = MotionEventCompat.getAxisValue(event, MotionEventCompat.AXIS_HSCROLL);
					if (vscroll != 0) {
						int newScrollY = getScrollY(), oldScrollY = newScrollY;
						int newScrollX = getScrollX(), oldScrollX = newScrollX;
						if (canScrollHorizontally()) {
							final int rangeX = getScrollRangeX();
							final int deltaX = (int) (hscroll * getHorizontalScrollFactorCompat());
							newScrollX = oldScrollX - deltaX;
							if (newScrollX < 0) {
								newScrollX = 0;
							} else if (newScrollX > rangeX) {
								newScrollX = rangeX;
							}
						}
						if (canScrollVertically()) {
							final int deltaY = (int) (vscroll * getVerticalScrollFactorCompat());
							final int rangeY = getScrollRangeY();
							newScrollY = oldScrollY - deltaY;
							if (newScrollY < 0) {
								newScrollY = 0;
							} else if (newScrollY > rangeY) {
								newScrollY = rangeY;
							}
						}
						if (newScrollY != oldScrollY || newScrollX != oldScrollX) {
							super.scrollTo(newScrollX, newScrollY);
							return true;
						}
					}
				}
			}
		}
		return false;
	}

	private float getVerticalScrollFactorCompat() {
		if (mVerticalScrollFactor == 0) {
			TypedValue outValue = new TypedValue();
			final Context context = getContext();
			if (!context.getTheme().resolveAttribute(
					android.R.attr.listPreferredItemHeight, outValue, true)) {
				throw new IllegalStateException(
						"Expected theme to define listPreferredItemHeight.");
			}
			mVerticalScrollFactor = outValue.getDimension(
					context.getResources().getDisplayMetrics());
		}
		return mVerticalScrollFactor;
	}

	private float getHorizontalScrollFactorCompat() {
		if (mVerticalScrollFactor == 0) {
			TypedValue outValue = new TypedValue();
			final Context context = getContext();
			if (!context.getTheme().resolveAttribute(
					android.R.attr.listPreferredItemHeight, outValue, true)) {
				throw new IllegalStateException(
						"Expected theme to define listPreferredItemHeight.");
			}
			mVerticalScrollFactor = outValue.getDimension(
					context.getResources().getDisplayMetrics());
		}
		return mVerticalScrollFactor;
	}

	protected void onOverScrolled(int scrollX, int scrollY,
								  boolean clampedX, boolean clampedY) {
		super.scrollTo(scrollX, scrollY);
	}

	boolean overScrollByCompat(int deltaX, int deltaY,
							   int scrollX, int scrollY,
							   int scrollRangeX, int scrollRangeY,
							   int maxOverScrollX, int maxOverScrollY,
							   boolean isTouchEvent) {
		int oldScrollX = getScrollX();
		int oldScrollY = getScrollY();

		final int overScrollMode = ViewCompat.getOverScrollMode(this);
		final boolean canScrollHorizontal =
				computeHorizontalScrollRange() > computeHorizontalScrollExtent() && canScrollHorizontally();
		final boolean canScrollVertical =
				computeVerticalScrollRange() > computeVerticalScrollExtent() && canScrollVertically();
		final boolean overScrollHorizontal = overScrollMode == ViewCompat.OVER_SCROLL_ALWAYS ||
				(overScrollMode == ViewCompat.OVER_SCROLL_IF_CONTENT_SCROLLS && canScrollHorizontal);
		final boolean overScrollVertical = overScrollMode == ViewCompat.OVER_SCROLL_ALWAYS ||
				(overScrollMode == ViewCompat.OVER_SCROLL_IF_CONTENT_SCROLLS && canScrollVertical);

		int newScrollX = scrollX;
		if (canScrollHorizontally()) {
			newScrollX += deltaX;
		}

		int newScrollY = scrollY;
		if (canScrollVertically()) {
			newScrollY += deltaY;
		}

		// Clamp values if at the limits and record
		final int left = -maxOverScrollX;
		final int right = maxOverScrollX + scrollRangeX;
		final int top = -maxOverScrollY;
		final int bottom = maxOverScrollY + scrollRangeY;

		boolean clampedX = false;
		if (newScrollX > right) {
			newScrollX = right;
			clampedX = true;
		} else if (newScrollX < left) {
			newScrollX = left;
			clampedX = true;
		}

		boolean clampedY = false;
		if (newScrollY > bottom) {
			newScrollY = bottom;
			clampedY = true;
		} else if (newScrollY < top) {
			newScrollY = top;
			clampedY = true;
		}

		if (clampedY && clampedX) {
			mScroller.springBack(newScrollX, newScrollY, 0, getScrollRangeX(), 0, getScrollRangeY());
		}

		onOverScrolled(newScrollX, newScrollY, clampedX, clampedY);

		return getScrollX() - oldScrollX == deltaX || getScrollY() - oldScrollY == deltaY;
	}

	private int getScrollRangeY() {
		int scrollRange = 0;
		if (getChildCount() > 0) {
			View child = getChildAt(0);
			scrollRange = Math.max(0, child.getHeight() - (getHeight() - getPaddingBottom() - getPaddingTop()));
		}
		return scrollRange;
	}

	private int getScrollRangeX() {
		int scrollRange = 0;
		if (getChildCount() > 0) {
			View child = getChildAt(0);
			scrollRange = Math.max(0, child.getWidth() - (getWidth() - getPaddingLeft() - getPaddingRight()));
		}
		return scrollRange;
	}

	/**
	 *
	 * Finds the next focusable component that fits in the specified bounds.
	 *
	 *
	 * @param topFocus look for a candidate is the one at the top of the bounds
	 *                 if topFocus is true, or at the bottom of the bounds if topFocus is
	 *                 false
	 * @param top      the top offset of the bounds in which a focusable must be
	 *                 found
	 * @param bottom   the bottom offset of the bounds in which a focusable must
	 *                 be found
	 * @return the next focusable component in the bounds or null if none can
	 * be found
	 */
	private View findFocusableViewInBoundsVertically(boolean topFocus, int top, int bottom) {

		List<View> focusables = getFocusables(View.FOCUS_FORWARD);
		View focusCandidate = null;

        /*
         * A fully contained focusable is one where its top is below the bound's
         * top, and its bottom is above the bound's bottom. A partially
         * contained focusable is one where some part of it is within the
         * bounds, but it also has some part that is not within bounds.  A fully contained
         * focusable is preferred to a partially contained focusable.
         */
		boolean foundFullyContainedFocusable = false;

		int count = focusables.size();
		for (int i = 0; i < count; i++) {
			View view = focusables.get(i);
			int viewTop = view.getTop();
			int viewBottom = view.getBottom();

			if (top < viewBottom && viewTop < bottom) {
                /*
                 * the focusable is in the target area, it is a candidate for
                 * focusing
                 */

				final boolean viewIsFullyContained = (top < viewTop) &&
						(viewBottom < bottom);

				if (focusCandidate == null) {
                    /* No candidate, take this one */
					focusCandidate = view;
					foundFullyContainedFocusable = viewIsFullyContained;
				} else {
					final boolean viewIsCloserToBoundary =
							(topFocus && viewTop < focusCandidate.getTop()) ||
									(!topFocus && viewBottom > focusCandidate
											.getBottom());

					if (foundFullyContainedFocusable) {
						if (viewIsFullyContained && viewIsCloserToBoundary) {
                            /*
                             * We're dealing with only fully contained views, so
                             * it has to be closer to the boundary to beat our
                             * candidate
                             */
							focusCandidate = view;
						}
					} else {
						if (viewIsFullyContained) {
                            /* Any fully contained view beats a partially contained view */
							focusCandidate = view;
							foundFullyContainedFocusable = true;
						} else if (viewIsCloserToBoundary) {
                            /*
                             * Partially contained view beats another partially
                             * contained view if it's closer
                             */
							focusCandidate = view;
						}
					}
				}
			}
		}

		return focusCandidate;
	}

	private View findFocusableViewInBoundsHorizontally(boolean topFocus, int left, int right) {
		List<View> focusables = getFocusables(View.FOCUS_FORWARD);
		View focusCandidate = null;

        /*
         * A fully contained focusable is one where its top is below the bound's
         * top, and its bottom is above the bound's bottom. A partially
         * contained focusable is one where some part of it is within the
         * bounds, but it also has some part that is not within bounds.  A fully contained
         * focusable is preferred to a partially contained focusable.
         */
		boolean foundFullyContainedFocusable = false;

		int count = focusables.size();
		for (int i = 0; i < count; i++) {
			View view = focusables.get(i);
			int viewLeft = view.getLeft();
			int viewRight = view.getRight();

			if (left < viewRight && viewLeft < viewRight) {
                /*
                 * the focusable is in the target area, it is a candidate for
                 * focusing
                 */

				final boolean viewIsFullyContained = (left < viewLeft) &&
						(viewRight < right);

				if (focusCandidate == null) {
                    /* No candidate, take this one */
					focusCandidate = view;
					foundFullyContainedFocusable = viewIsFullyContained;
				} else {
					final boolean viewIsCloserToBoundary =
							(topFocus && viewLeft < focusCandidate.getTop()) ||
									(!topFocus && viewRight > focusCandidate
											.getBottom());

					if (foundFullyContainedFocusable) {
						if (viewIsFullyContained && viewIsCloserToBoundary) {
                            /*
                             * We're dealing with only fully contained views, so
                             * it has to be closer to the boundary to beat our
                             * candidate
                             */
							focusCandidate = view;
						}
					} else {
						if (viewIsFullyContained) {
                            /* Any fully contained view beats a partially contained view */
							focusCandidate = view;
							foundFullyContainedFocusable = true;
						} else if (viewIsCloserToBoundary) {
                            /*
                             * Partially contained view beats another partially
                             * contained view if it's closer
                             */
							focusCandidate = view;
						}
					}
				}
			}
		}

		return focusCandidate;
	}

	/**
	 * Handles scrolling in response to a "page up/down" shortcut press. This
	 * method will scroll the view by one page up or down and give the focus
	 * to the topmost/bottommost component in the new visible area. If no
	 * component is a good candidate for focus, this scrollview reclaims the
	 * focus.
	 *
	 * @param direction the scroll direction: {@link View#FOCUS_UP}
	 *                  to go one page up or
	 *                  {@link View#FOCUS_DOWN} to go one page down
	 * @return true if the key event is consumed by this method, false otherwise
	 */
	public boolean pageScrollHorizontally(int direction) {
		boolean down = direction == View.FOCUS_DOWN;
		int width = getWidth();

		if (down) {
			mTempRect.left = getScrollX() + width;
			int count = getChildCount();
			if (count > 0) {
				View view = getChildAt(count - 1);
				if (mTempRect.left + width > view.getRight()) {
					mTempRect.left = view.getRight() - width;
				}
			}
		} else {
			mTempRect.left = getScrollY() - width;
			if (mTempRect.left < 0) {
				mTempRect.left = 0;
			}
		}
		mTempRect.right = mTempRect.left + width;
		return scrollAndFocusHorizontally(direction, mTempRect.left, mTempRect.right);
	}

	public boolean pageScrollVertically(int direction) {
		boolean down = direction == View.FOCUS_DOWN;
		int height = getHeight();

		if (down) {
			mTempRect.top = getScrollY() + height;
			int count = getChildCount();
			if (count > 0) {
				View view = getChildAt(count - 1);
				if (mTempRect.top + height > view.getBottom()) {
					mTempRect.top = view.getBottom() - height;
				}
			}
		} else {
			mTempRect.top = getScrollY() - height;
			if (mTempRect.top < 0) {
				mTempRect.top = 0;
			}
		}
		mTempRect.bottom = mTempRect.top + height;
		return scrollAndFocusVertically(direction, mTempRect.top, mTempRect.bottom);
	}

	/**
	 * Handles scrolling in response to a "home/end" shortcut press. This
	 * method will scroll the view to the top or bottom and give the focus
	 * to the topmost/bottommost component in the new visible area. If no
	 * component is a good candidate for focus, this scrollview reclaims the
	 * focus.
	 *
	 * @param direction the scroll direction: {@link View#FOCUS_UP}
	 *                  to go the top of the view or
	 *                  {@link View#FOCUS_DOWN} to go the bottom
	 * @return true if the key event is consumed by this method, false otherwise
	 */
	public boolean fullScrollVertically(int direction) {
		boolean down = direction == View.FOCUS_DOWN;
		int height = getHeight();

		mTempRect.top = 0;
		mTempRect.bottom = height;

		if (down) {
			int count = getChildCount();
			if (count > 0) {
				View view = getChildAt(count - 1);
				mTempRect.bottom = view.getBottom() + getPaddingBottom();
				mTempRect.top = mTempRect.bottom - height;
			}
		}

		return scrollAndFocusVertically(direction, mTempRect.top, mTempRect.bottom);
	}

	/**
	 * Handles scrolling in response to a "home/end" shortcut press. This
	 * method will scroll the view to the top or bottom and give the focus
	 * to the topmost/bottommost component in the new visible area. If no
	 * component is a good candidate for focus, this scrollview reclaims the
	 * focus.
	 *
	 * @param direction the scroll direction: {@link View#FOCUS_UP}
	 *                  to go the top of the view or
	 *                  {@link View#FOCUS_DOWN} to go the bottom
	 * @return true if the key event is consumed by this method, false otherwise
	 */
	public boolean fullScrollHorizontally(int direction) {
		boolean down = direction == View.FOCUS_RIGHT;
		int width = getWidth();

		mTempRect.left = 0;
		mTempRect.right = width;

		if (down) {
			int count = getChildCount();
			if (count > 0) {
				View view = getChildAt(count - 1);
				mTempRect.right = view.getRight() + getPaddingLeft();
				mTempRect.left = mTempRect.right - width;
			}
		}

		return scrollAndFocusHorizontally(direction, mTempRect.left, mTempRect.right);
	}


	private boolean scrollAndFocusHorizontally(int direction, int left, int right) {
		boolean handled = true;

		int width = getWidth();
		int containerLeft = getScrollX();
		int containerRight = containerLeft + width;
		boolean up = direction == View.FOCUS_LEFT;

		View newFocused = findFocusableViewInBoundsHorizontally(up, left, right);
		if (newFocused == null) {
			newFocused = this;
		}

		if (left >= containerLeft && right <= containerRight) {
			handled = false;
		} else {
			int delta = up ? (left - containerLeft) : (right - containerRight);
			doScrollX(delta);
		}

		if (newFocused != findFocus()) newFocused.requestFocus(direction);

		return handled;
	}

	/**
	 * Scrolls the view to make the area defined by <code>top</code> and
	 * <code>bottom</code> visible. This method attempts to give the focus
	 * to a component visible in this area. If no component can be focused in
	 * the new visible area, the focus is reclaimed by this ScrollView.
	 *
	 * @param direction the scroll direction: {@link View#FOCUS_UP}
	 *                  to go upward, {@link View#FOCUS_DOWN} to downward
	 * @param top       the top offset of the new area to be made visible
	 * @param bottom    the bottom offset of the new area to be made visible
	 * @return true if the key event is consumed by this method, false otherwise
	 */
	private boolean scrollAndFocusVertically(int direction, int top, int bottom) {
		boolean handled = true;

		int height = getHeight();
		int containerTop = getScrollY();
		int containerBottom = containerTop + height;
		boolean up = direction == View.FOCUS_UP;

		View newFocused = findFocusableViewInBoundsVertically(up, top, bottom);
		if (newFocused == null) {
			newFocused = this;
		}

		if (top >= containerTop && bottom <= containerBottom) {
			handled = false;
		} else {
			int delta = up ? (top - containerTop) : (bottom - containerBottom);
			doScrollY(delta);
		}

		if (newFocused != findFocus()) newFocused.requestFocus(direction);

		return handled;
	}

	/**
	 * Handle scrolling in response to an up or down arrow click.
	 *
	 * @param direction The direction corresponding to the arrow key that was
	 *                  pressed
	 * @return True if we consumed the event, false otherwise
	 */
	public boolean arrowScrollHorizontally(int direction) {

		View currentFocused = findFocus();
		if (currentFocused == this) currentFocused = null;

		View nextFocused = FocusFinder.getInstance().findNextFocus(this, currentFocused, direction);

		final int maxJump = getMaxScrollAmountX();

		if (nextFocused != null && isWithinDeltaOfScreenX(nextFocused, maxJump, getWidth())) {
			nextFocused.getDrawingRect(mTempRect);
			offsetDescendantRectToMyCoords(nextFocused, mTempRect);
			int[] scrollDelta = computeScrollDeltaToGetChildRectOnScreen(mTempRect);
			doScrollX(scrollDelta[0]);
			nextFocused.requestFocus(direction);
		} else {
			// no new focus
			int scrollDelta = maxJump;

			if (direction == View.FOCUS_UP && getScrollX() < scrollDelta) {
				scrollDelta = getScrollX();
			} else if (direction == View.FOCUS_DOWN) {
				if (getChildCount() > 0) {
					int daRight = getChildAt(0).getRight();
					int screenRight = getScrollX() + getWidth() - getPaddingRight();
					if (daRight - screenRight < maxJump) {
						scrollDelta = daRight - screenRight;
					}
				}
			}
			if (scrollDelta == 0) {
				return false;
			}
			doScrollX(direction == View.FOCUS_DOWN ? scrollDelta : -scrollDelta);
		}

		if (currentFocused != null && currentFocused.isFocused() && isOffScreenX(currentFocused)) {
			// previously focused item still has focus and is off screen, give
			// it up (take it back to ourselves)
			// (also, need to temporarily force FOCUS_BEFORE_DESCENDANTS so we are
			// sure to
			// get it)
			final int descendantFocusability = getDescendantFocusability();  // save
			setDescendantFocusability(ViewGroup.FOCUS_BEFORE_DESCENDANTS);
			requestFocus();
			setDescendantFocusability(descendantFocusability);  // restore
		}
		return true;
	}

	/**
	 * Handle scrolling in response to an up or down arrow click.
	 *
	 * @param direction The direction corresponding to the arrow key that was
	 *                  pressed
	 * @return True if we consumed the event, false otherwise
	 */
	public boolean arrowScrollVertically(int direction) {

		View currentFocused = findFocus();
		if (currentFocused == this) currentFocused = null;

		View nextFocused = FocusFinder.getInstance().findNextFocus(this, currentFocused, direction);

		final int maxJump = getMaxScrollAmountY();

		if (nextFocused != null && isWithinDeltaOfScreenY(nextFocused, maxJump, getHeight())) {
			nextFocused.getDrawingRect(mTempRect);
			offsetDescendantRectToMyCoords(nextFocused, mTempRect);
			int[] scrollDelta = computeScrollDeltaToGetChildRectOnScreen(mTempRect);
			doScrollY(scrollDelta[1]);
			nextFocused.requestFocus(direction);
		} else {
			// no new focus
			int scrollDelta = maxJump;

			if (direction == View.FOCUS_UP && getScrollY() < scrollDelta) {
				scrollDelta = getScrollY();
			} else if (direction == View.FOCUS_DOWN) {
				if (getChildCount() > 0) {
					int daBottom = getChildAt(0).getBottom();
					int screenBottom = getScrollY() + getHeight() - getPaddingBottom();
					if (daBottom - screenBottom < maxJump) {
						scrollDelta = daBottom - screenBottom;
					}
				}
			}
			if (scrollDelta == 0) {
				return false;
			}
			doScrollY(direction == View.FOCUS_DOWN ? scrollDelta : -scrollDelta);
		}

		if (currentFocused != null && currentFocused.isFocused()
				&& isOffScreenY(currentFocused)) {
			// previously focused item still has focus and is off screen, give
			// it up (take it back to ourselves)
			// (also, need to temporarily force FOCUS_BEFORE_DESCENDANTS so we are
			// sure to
			// get it)
			final int descendantFocusability = getDescendantFocusability();  // save
			setDescendantFocusability(ViewGroup.FOCUS_BEFORE_DESCENDANTS);
			requestFocus();
			setDescendantFocusability(descendantFocusability);  // restore
		}
		return true;
	}

	/**
	 * @return whether the descendant of this scroll view is scrolled off
	 * screen.
	 */
	private boolean isOffScreenX(View descendant) {
		return !isWithinDeltaOfScreenX(descendant, 0, getWidth());
	}


	/**
	 * @return whether the descendant of this scroll view is scrolled off
	 * screen.
	 */
	private boolean isOffScreenY(View descendant) {
		return !isWithinDeltaOfScreenY(descendant, 0, getHeight());
	}

	/**
	 * @return whether the descendant of this scroll view is within delta
	 * pixels of being on the screen.
	 */
	private boolean isWithinDeltaOfScreenX(View descendant, int delta, int width) {
		descendant.getDrawingRect(mTempRect);
		offsetDescendantRectToMyCoords(descendant, mTempRect);

		return (mTempRect.right + delta) >= getScrollX()
				&& (mTempRect.left - delta) <= (getScrollX() + width);
	}

	/**
	 * @return whether the descendant of this scroll view is within delta
	 * pixels of being on the screen.
	 */
	private boolean isWithinDeltaOfScreenY(View descendant, int delta, int height) {
		descendant.getDrawingRect(mTempRect);
		offsetDescendantRectToMyCoords(descendant, mTempRect);

		return (mTempRect.bottom + delta) >= getScrollY()
				&& (mTempRect.top - delta) <= (getScrollY() + height);
	}

	private void doScrollXY(int[] delta) {
		doScrollXY(delta[0], delta[1]);
	}

	private void doScrollXY(int deltaX, int deltaY) {
		if (deltaX != 0 || deltaY != 0) {
			if (mSmoothScrollingEnabled) {
				smoothScrollBy(deltaX, deltaY);
			} else {
				scrollBy(deltaX, deltaY);
			}
		}
	}

	/**
	 * Smooth scroll by a Y delta
	 *
	 * @param delta the number of pixels to scroll by on the Y axis
	 */
	private void doScrollY(int delta) {
		if (delta != 0) {
			if (mSmoothScrollingEnabled) {
				smoothScrollBy(0, delta);
			} else {
				scrollBy(0, delta);
			}
		}
	}

	private void doScrollX(int delta) {
		if (delta != 0) {
			if (mSmoothScrollingEnabled) {
				smoothScrollBy(delta, 0);
			} else {
				scrollBy(delta, 0);
			}
		}
	}

	/**
	 * Like {@link View#scrollBy}, but scroll smoothly instead of immediately.
	 *
	 * @param dx the number of pixels to scroll by on the X axis
	 * @param dy the number of pixels to scroll by on the Y axis
	 */
	public final void smoothScrollBy(int dx, int dy) {
		if (getChildCount() == 0) {
			// Nothing to do.
			return;
		}
		long duration = AnimationUtils.currentAnimationTimeMillis() - mLastScroll;
		if (duration > ANIMATED_SCROLL_GAP) {
			setScrollState(SCROLL_STATE_SETTLING);

			final int height = getHeight() - getPaddingBottom() - getPaddingTop();
			final int bottom = getChildAt(0).getHeight();
			final int width = getWidth() - getPaddingRight() - getPaddingLeft();
			final int right = getChildAt(0).getWidth();
			final int maxY = Math.max(0, bottom - height);
			final int maxX = Math.max(0, right - width);
			final int scrollY = getScrollY();
			final int scrollX = getScrollX();
			dy = Math.max(0, Math.min(scrollY + dy, maxY)) - scrollY;
			dx = Math.max(0, Math.min(scrollX + dx, maxX)) - scrollX;

			mScroller.startScroll(scrollX, scrollY, dx, dy);
			ViewCompat.postInvalidateOnAnimation(this);
		} else {
			setScrollState(SCROLL_STATE_IDLE);
			if (!mScroller.isFinished()) {
				mScroller.abortAnimation();
			}
			scrollBy(dx, dy);
		}
		mLastScroll = AnimationUtils.currentAnimationTimeMillis();
	}

	/**
	 * Like {@link #scrollTo}, but scroll smoothly instead of immediately.
	 *
	 * @param x the position where to scroll on the X axis
	 * @param y the position where to scroll on the Y axis
	 */
	public final void smoothScrollTo(int x, int y) {
		smoothScrollBy(x - getScrollX(), y - getScrollY());
	}


	/**
	 * The scroll range of a scroll view is the overall height of all of its
	 * children.
	 */
	@Override
	public int computeVerticalScrollRange() {
		if (!canScrollVertically()) {
			return super.computeVerticalScrollRange();
		}
		final int count = getChildCount();
		final int contentHeight = getHeight() - getPaddingBottom() - getPaddingTop();
		if (count == 0) {
			return contentHeight;
		}

		int scrollRange = getChildAt(0).getBottom();
		final int scrollY = getScrollY();
		final int overscrollBottom = Math.max(0, scrollRange - contentHeight);
		if (scrollY < 0) {
			scrollRange -= scrollY;
		} else if (scrollY > overscrollBottom) {
			scrollRange += scrollY - overscrollBottom;
		}

		return scrollRange;
	}

	/**
	 *
	 */
	@Override
	public int computeVerticalScrollOffset() {
		return Math.max(0, super.computeVerticalScrollOffset());
	}

	/**
	 *
	 */
	@Override
	public int computeVerticalScrollExtent() {
		return super.computeVerticalScrollExtent();
	}

	/**
	 *
	 */
	@Override
	public int computeHorizontalScrollRange() {
		if (!canScrollHorizontally()) {
			return super.computeHorizontalScrollRange();
		}
		final int count = getChildCount();
		final int contentWidth = getWidth() - getPaddingRight() - getPaddingLeft();
		if (count == 0) {
			return contentWidth;
		}

		int scrollRange = getChildAt(0).getRight();
		final int scrollX = getScrollX();
		final int overscrollRight = Math.max(0, scrollRange - contentWidth);
		if (scrollX < 0) {
			scrollRange -= scrollX;
		} else if (scrollX > overscrollRight) {
			scrollRange += scrollX - overscrollRight;
		}
		return scrollRange;
	}

	/**
	 *
	 */
	@Override
	public int computeHorizontalScrollOffset() {
		return Math.max(0, super.computeHorizontalScrollOffset());
	}

	/**
	 *
	 */
	@Override
	public int computeHorizontalScrollExtent() {
		return super.computeHorizontalScrollExtent();
	}

	@Override
	protected void onLayout(boolean changed, int l, int t, int r, int b) {
		if (getChildCount() == 0) {
			return;
		}
		View child = getChildAt(0);
		final MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams();

		int childLeft = getPaddingLeft() + lp.leftMargin;
		int childTop = getPaddingTop() + lp.topMargin;
		if (mChildLayoutCenter) {
			if (getMeasuredWidth() > child.getMeasuredWidth()) {
				childLeft = (getMeasuredWidth() - child.getMeasuredWidth()) / 2;
			}
			if (getMeasuredHeight() > child.getMeasuredHeight()) {
				childTop = (getMeasuredHeight() - child.getMeasuredHeight()) / 2;
			}
		}
		int measureHeight = child.getMeasuredHeight();
		int measuredWidth = child.getMeasuredWidth();
		child.layout(childLeft, childTop, measuredWidth + childLeft, childTop + measureHeight);


		mIsLayoutDirty = false;
		// Give a child focus if it needs it
		if (mChildToScrollTo != null && isViewDescendantOf(mChildToScrollTo, this)) {
			scrollToChild(mChildToScrollTo);
		}
		mChildToScrollTo = null;

		if (!mIsLaidOut) {
			if (mSavedState != null) {
				scrollTo(mSavedState.scrollXPosition, mSavedState.scrollYPosition);
				mSavedState = null;
			} // mScrollY default value is "0"

			final int childHeight = (getChildCount() > 0) ? getChildAt(0).getMeasuredHeight() : 0;
			final int scrollRangeY = Math.max(0,
					childHeight - (b - t - getPaddingBottom() - getPaddingTop()));

			final int childWidth = (getChildCount() > 0) ? getChildAt(0).getMeasuredWidth() : 0;
			final int scrollRangeX = Math.max(0,
					childWidth - (b - t - getPaddingRight() - getPaddingLeft()));

			int sY = getScrollY();
			int sX = getScrollX();

			// Don't forget to clamp
			if (getScrollY() > scrollRangeY) {
				sY = scrollRangeY;
			} else if (getScrollY() < 0) {
				sY = 0;
			}
			if (getScrollX() > scrollRangeX) {
				sX = scrollRangeX;
			} else if (getScrollX() < 0) {
				sX = 0;
			}
			if (sX != getScrollX() || sY != getScrollY()) {
				scrollTo(sX, sY);
			}
		}

		// Calling this with the present values causes it to re-claim them
		scrollTo(getScrollX(), getScrollY());
		mIsLaidOut = true;
	}

	@Override
	public MarginLayoutParams generateLayoutParams(AttributeSet attrs) {
		return new MarginLayoutParams(getContext(), attrs);
	}

	/**
	 * {@inheritDoc}
	 */
	@Override
	protected boolean checkLayoutParams(LayoutParams p) {
		return p instanceof MarginLayoutParams;
	}

	@Override
	protected MarginLayoutParams generateLayoutParams(LayoutParams p) {
		return new MarginLayoutParams(p);
	}

	@Override
	protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
		if (getChildCount() == 0) {
			return;
		}
		View child = getChildAt(0);
		MarginLayoutParams lp = (MarginLayoutParams) child.getLayoutParams();

		int widthPadding = lp.leftMargin + lp.rightMargin + getPaddingLeft() + getPaddingRight();
		int heightPadding = lp.topMargin + lp.bottomMargin + getPaddingTop() + getPaddingBottom();
		int maxWidth = widthPadding;
		int maxHeight = heightPadding;
		maxHeight = Math.max(maxHeight, getSuggestedMinimumHeight());
		maxWidth = Math.max(maxWidth, getSuggestedMinimumWidth());

		int childState = 0;
		int childWidthMeasureSpec;
		int childHeightMeasureSpec;

		if (canScrollVertically()) {
			childHeightMeasureSpec = MeasureSpec.makeMeasureSpec(
					MeasureSpec.getSize(heightMeasureSpec), MeasureSpec.UNSPECIFIED);
		} else {
			childHeightMeasureSpec = getChildMeasureSpec(heightMeasureSpec,
					getPaddingBottom() + getPaddingTop() + lp.topMargin + lp.bottomMargin, lp.height);
		}
		if (canScrollHorizontally()) {
			childWidthMeasureSpec = MeasureSpec.makeMeasureSpec(
					MeasureSpec.getSize(widthMeasureSpec), MeasureSpec.UNSPECIFIED);
		} else {
			childWidthMeasureSpec = getChildMeasureSpec(widthMeasureSpec,
					getPaddingLeft() + getPaddingRight() + lp.leftMargin + lp.rightMargin, lp.width);
		}
		child.measure(childWidthMeasureSpec, childHeightMeasureSpec);

		if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
			childState = combineMeasuredStates(childState, child.getMeasuredState());
		}
		maxWidth = Math.max(maxWidth, child.getMeasuredWidth() + lp.leftMargin + lp.rightMargin);
		maxHeight = Math.max(maxHeight, child.getMeasuredHeight() + lp.topMargin + lp.bottomMargin);

		maxHeight = Math.max(maxHeight, getSuggestedMinimumHeight());
		maxWidth = Math.max(maxWidth, getSuggestedMinimumWidth());

		int measuredWidth = ViewCompat.resolveSizeAndState(maxWidth, widthMeasureSpec, childState);
		int measuredHeight = ViewCompat.resolveSizeAndState(maxHeight, heightMeasureSpec, childState << MEASURED_HEIGHT_STATE_SHIFT);
		setMeasuredDimension(measuredWidth, measuredHeight);


		boolean needMeasure = false;
		final int heightMode = MeasureSpec.getMode(heightMeasureSpec);
		if (heightMode != MeasureSpec.UNSPECIFIED && mFillViewportV) {
			if (child.getMeasuredHeight() < measuredHeight - heightPadding) {
				int newChildHeightMeasureSpec = MeasureSpec.makeMeasureSpec(measuredHeight - heightPadding, MeasureSpec.EXACTLY);
				if (newChildHeightMeasureSpec != childHeightMeasureSpec) {
					childHeightMeasureSpec = newChildHeightMeasureSpec;
					needMeasure = true;
				}
			}
		}
		final int widthMode = MeasureSpec.getMode(widthMeasureSpec);
		if (widthMode != MeasureSpec.UNSPECIFIED && mFillViewportH) {
			if (child.getMeasuredWidth() < measuredWidth - widthPadding) {
				int newChildWidthMeasureSpec = MeasureSpec.makeMeasureSpec(measuredWidth - widthPadding, MeasureSpec.EXACTLY);
				if (newChildWidthMeasureSpec != childWidthMeasureSpec) {
					childWidthMeasureSpec = newChildWidthMeasureSpec;
					needMeasure = true;
				}
			}
		}
		if (needMeasure) {
			child.measure(childWidthMeasureSpec, childHeightMeasureSpec);
		}
	}

	@Override
	public void computeScroll() {
		if (mScroller.computeScrollOffset()) {
			int oldX = getScrollX();
			int oldY = getScrollY();
			int x = mScroller.getCurrX();
			int y = mScroller.getCurrY();

			if (oldX != x || oldY != y) {
				final int rangeY = getScrollRangeY();
				final int rangeX = getScrollRangeX();
				final int overscrollMode = ViewCompat.getOverScrollMode(this);
				final boolean canOverscrollY = overscrollMode == ViewCompat.OVER_SCROLL_ALWAYS ||
						(overscrollMode == ViewCompat.OVER_SCROLL_IF_CONTENT_SCROLLS && rangeY > 0);
				final boolean canOverscrollX = overscrollMode == ViewCompat.OVER_SCROLL_ALWAYS ||
						(overscrollMode == ViewCompat.OVER_SCROLL_IF_CONTENT_SCROLLS && rangeX > 0);
				boolean canOverscroll = canOverscrollY || canOverscrollX;

				overScrollByCompat(x - oldX, y - oldY, oldX, oldY, rangeX, rangeY,
						0, 0, false);

				if (canOverscroll) {
					ensureGlows();
					if (y <= 0 && oldY > 0) {
						mEdgeGlowTop.onAbsorb((int) mScroller.getCurrVelocity());
					} else if (y >= rangeY && oldY < rangeY) {
						mEdgeGlowBottom.onAbsorb((int) mScroller.getCurrVelocity());
					}

					if (x <= 0 && oldX > 0) {
						mEdgeGlowLeft.onAbsorb((int) mScroller.getCurrVelocity());
					} else if (x >= rangeX && oldX < rangeX) {
						mEdgeGlowRight.onAbsorb((int) mScroller.getCurrVelocity());
					}
				}
			}

//            final boolean fullyConsumedVertical = canScrollVertically()
//                    && x == getScrollX();
//            final boolean fullyConsumedHorizontal = canScrollHorizontally()
//                    && x == getScrollY();
//            final boolean fullyConsumedAny = fullyConsumedHorizontal
//                    || fullyConsumedVertical;

			if (mScroller.isFinished()) {
				setScrollState(SCROLL_STATE_IDLE); // setting state to idle will stop this.
			} else {
				ViewCompat.postInvalidateOnAnimation(this);
			}
		}
	}

	/**
	 * Scrolls the view to the given child.
	 *
	 * @param child the View to scroll to
	 */
	private void scrollToChild(View child) {
		child.getDrawingRect(mTempRect);

        /* Offset from child's local coordinates to ScrollView coordinates */
		offsetDescendantRectToMyCoords(child, mTempRect);

		int scrollDelta[] = computeScrollDeltaToGetChildRectOnScreen(mTempRect);

		if (scrollDelta[0] != 0 || scrollDelta[1] != 0) {
			scrollBy(scrollDelta[0], scrollDelta[1]);
		}
	}

	/**
	 * If rect is off screen, scroll just enough to get it (or at least the
	 * first screen size chunk of it) on screen.
	 *
	 * @param rect      The rectangle.
	 * @param immediate True to scroll immediately without animation
	 * @return true if scrolling was performed
	 */
	private boolean scrollToChildRect(Rect rect, boolean immediate) {
		final int delta[] = computeScrollDeltaToGetChildRectOnScreen(rect);
		final boolean scroll = delta[0] != 0 || delta[1] != 0;
		if (scroll) {
			if (immediate) {
				scrollBy(delta[0], delta[1]);
			} else {
				smoothScrollBy(delta[0], delta[1]);
			}
		}
		return scroll;
	}

	/**
	 * Compute the amount to scroll in the Y direction in order to get
	 * a rectangle completely on the screen (or, if taller than the screen,
	 * at least the first screen size chunk of it).
	 *
	 * @param rect The rect.
	 * @return The scroll delta.
	 */
	protected int[] computeScrollDeltaToGetChildRectOnScreen(Rect rect) {
		if (getChildCount() == 0) return new int[]{0, 0};

		int height = getHeight();
		int width = getWidth();
		int screenTop = getScrollY();
		int screenBottom = screenTop + height;
		int screenLeft = getScrollX();
		int screenRight = screenLeft + width;

		int fadingEdgeY = getVerticalFadingEdgeLength();
		int fadingEdgeX = getHorizontalFadingEdgeLength();

		// leave room for top fading edge as long as rect isn't at very top
		if (rect.top > 0) {
			screenTop += fadingEdgeY;
		}
		if (rect.left > 0) {
			screenLeft += fadingEdgeX;
		}

		// leave room for bottom fading edge as long as rect isn't at very bottom
		if (rect.bottom < getChildAt(0).getHeight()) {
			screenBottom -= fadingEdgeY;
		}
		if (rect.right < getChildAt(0).getWidth()) {
			screenRight -= fadingEdgeX;
		}

		int scrollYDelta = 0;
		int scrollXDelta = 0;

		if (rect.bottom > screenBottom && rect.top > screenTop) {
			// need to move down to get it in view: move down just enough so
			// that the entire rectangle is in view (or at least the first
			// screen size chunk).

			if (rect.height() > height) {
				// just enough to get screen size chunk on
				scrollYDelta += (rect.top - screenTop);
			} else {
				// get entire rect at bottom of screen
				scrollYDelta += (rect.bottom - screenBottom);
			}

			// make sure we aren't scrolling beyond the end of our content
			int bottom = getChildAt(0).getBottom();
			int distanceToBottom = bottom - screenBottom;
			scrollYDelta = Math.min(scrollYDelta, distanceToBottom);

		} else if (rect.top < screenTop && rect.bottom < screenBottom) {
			// need to move up to get it in view: move up just enough so that
			// entire rectangle is in view (or at least the first screen
			// size chunk of it).

			if (rect.height() > height) {
				// screen size chunk
				scrollYDelta -= (screenBottom - rect.bottom);
			} else {
				// entire rect at top
				scrollYDelta -= (screenTop - rect.top);
			}

			// make sure we aren't scrolling any further than the top our content
			scrollYDelta = Math.max(scrollYDelta, -getScrollY());
		}
		if (rect.right > screenRight && rect.left > screenLeft) {
			// need to move down to get it in view: move down just enough so
			// that the entire rectangle is in view (or at least the first
			// screen size chunk).

			if (rect.width() > width) {
				// just enough to get screen size chunk on
				scrollXDelta += (rect.left - screenLeft);
			} else {
				// get entire rect at bottom of screen
				scrollXDelta += (rect.right - screenRight);
			}

			// make sure we aren't scrolling beyond the end of our content
			int right = getChildAt(0).getRight();
			int distanceToRight = right - screenRight;
			scrollXDelta = Math.min(scrollXDelta, distanceToRight);

		} else if (rect.left < screenLeft && rect.right < screenRight) {
			// need to move up to get it in view: move up just enough so that
			// entire rectangle is in view (or at least the first screen
			// size chunk of it).

			if (rect.width() > width) {
				// screen size chunk
				scrollXDelta -= (screenRight - rect.right);
			} else {
				// entire rect at top
				scrollXDelta -= (screenLeft - rect.left);
			}

			// make sure we aren't scrolling any further than the top our content
			scrollXDelta = Math.max(scrollXDelta, -getScrollX());
		}
		return new int[]{scrollXDelta, scrollYDelta};
	}

	@Override
	public void requestChildFocus(View child, View focused) {
		if (!mIsLayoutDirty) {
			scrollToChild(focused);
		} else {
			// The child may not be laid out yet, we can't compute the scroll yet
			mChildToScrollTo = focused;
		}
		super.requestChildFocus(child, focused);
	}


	/**
	 * When looking for focus in children of a scroll view, need to be a little
	 * more careful not to give focus to something that is scrolled off screen.
	 *
	 * This is more expensive than the default {@link ViewGroup}
	 * implementation, otherwise this behavior might have been made the default.
	 */
	@Override
	protected boolean onRequestFocusInDescendants(int direction,
												  Rect previouslyFocusedRect) {

		// convert from forward / backward notation to up / down / left / right
		// (ugh).
		if (direction == View.FOCUS_FORWARD) {
			direction = View.FOCUS_DOWN;
		} else if (direction == View.FOCUS_BACKWARD) {
			direction = View.FOCUS_UP;
		}

		final View nextFocus = previouslyFocusedRect == null ?
				FocusFinder.getInstance().findNextFocus(this, null, direction) :
				FocusFinder.getInstance().findNextFocusFromRect(this,
						previouslyFocusedRect, direction);

		if (nextFocus == null) {
			return false;
		}

		if (canScrollHorizontally()) {
			if (isOffScreenX(nextFocus)) {
				return false;
			}
		} else if (canScrollVertically()) {
			if (isOffScreenY(nextFocus)) {
				return false;
			}
		}

		return nextFocus.requestFocus(direction, previouslyFocusedRect);
	}

	@Override
	public boolean requestChildRectangleOnScreen(View child, Rect rectangle,
												 boolean immediate) {
		// offset into coordinate space of this scroll view
		rectangle.offset(child.getLeft() - child.getScrollX(),
				child.getTop() - child.getScrollY());

		return scrollToChildRect(rectangle, immediate);
	}

	@Override
	public void requestLayout() {
		mIsLayoutDirty = true;
		super.requestLayout();
	}

	@Override
	public void onAttachedToWindow() {
		super.onAttachedToWindow();

		mIsLaidOut = false;
	}

	@Override
	protected void onSizeChanged(int w, int h, int oldw, int oldh) {
		super.onSizeChanged(w, h, oldw, oldh);

		View currentFocused = findFocus();
		if (null == currentFocused || this == currentFocused)
			return;

		// If the currently-focused view was visible on the screen when the
		// screen was at the old height, then scroll the screen to make that
		// view visible with the new screen height.
		if (isWithinDeltaOfScreenX(currentFocused, 0, oldw) || isWithinDeltaOfScreenY(currentFocused, 0, oldh)) {
			currentFocused.getDrawingRect(mTempRect);
			offsetDescendantRectToMyCoords(currentFocused, mTempRect);
			int scrollDelta[] = computeScrollDeltaToGetChildRectOnScreen(mTempRect);
			doScrollXY(scrollDelta);
		}
	}

	/**
	 * Return true if child is a descendant of parent, (or equal to the parent).
	 */
	private static boolean isViewDescendantOf(View child, View parent) {
		if (child == parent) {
			return true;
		}

		final ViewParent theParent = child.getParent();
		return (theParent instanceof ViewGroup) && isViewDescendantOf((View) theParent, parent);
	}

	private boolean fling(int velocityX, int velocityY) {
		final boolean canScrollHorizontal = canScrollHorizontally();
		final boolean canScrollVertical = canScrollVertically();

		if (!canScrollHorizontal || Math.abs(velocityX) < mMinimumVelocity) {
			velocityX = 0;
		}
		if (!canScrollVertical || Math.abs(velocityY) < mMinimumVelocity) {
			velocityY = 0;
		}
		if (velocityX == 0 && velocityY == 0) {
			// If we don't have any velocity, return false
			return false;
		}

		if (!dispatchNestedPreFling(velocityX, velocityY)) {
			final int scrollY = getScrollY();
			final int scrollX = getScrollX();
			final boolean canFlingY = (scrollY > 0 || velocityY > 0) &&
					(scrollY < getScrollRangeY() || velocityY < 0);
			final boolean canFlingX = (scrollX > 0 || velocityX > 0) &&
					(scrollX < getScrollRangeX() || velocityX < 0);
			boolean canFling = canFlingY || canFlingX;
			dispatchNestedFling(velocityX, velocityY, canFling);
			if (canFling) {
				setScrollState(SCROLL_STATE_SETTLING);

				velocityX = Math.max(-mMaximumVelocity, Math.min(velocityX, mMaximumVelocity));
				velocityY = Math.max(-mMaximumVelocity, Math.min(velocityY, mMaximumVelocity));

				int height = getHeight() - getPaddingBottom() - getPaddingTop();
				int width = getWidth() - getPaddingRight() - getPaddingLeft();
				int bottom = getChildAt(0).getHeight();
				int right = getChildAt(0).getWidth();
				mScroller.fling(getScrollX(), getScrollY(), velocityX, velocityY, 0, Math.max(0, right - width), 0,
						Math.max(0, bottom - height), width / 2, height / 2);

//                ViewCompat.postInvalidateOnAnimation(this);
				return true;
			}
		}
		return false;
	}

//    private void endDrag() {
//        mIsBeingDragged = false;
//
//        recycleVelocityTracker();
//        stopNestedScroll();
//
//        if (mEdgeGlowTop != null) {
//            mEdgeGlowTop.onRelease();
//            mEdgeGlowBottom.onRelease();
//            mEdgeGlowLeft.onRelease();
//            mEdgeGlowRight.onRelease();
//        }
//    }

	/**
	 * {@inheritDoc}
	 *
	 * This version also clamps the scrolling to the bounds of our child.
	 */
	@Override
	public void scrollTo(int x, int y) {
		// we rely on the fact the View.scrollBy calls scrollTo.
		if (getChildCount() > 0) {
			View child = getChildAt(0);
			x = clamp(x, getWidth() - getPaddingRight() - getPaddingLeft(), child.getWidth());
			y = clamp(y, getHeight() - getPaddingBottom() - getPaddingTop(), child.getHeight());
			if (x != getScrollX() || y != getScrollY()) {
				super.scrollTo(x, y);
			}
		}
	}

	private void ensureGlows() {
		if (ViewCompat.getOverScrollMode(this) != ViewCompat.OVER_SCROLL_NEVER) {
			if (mEdgeGlowTop == null) {
				Context context = getContext();
				mEdgeGlowTop = new EdgeEffectCompat(context);
				mEdgeGlowBottom = new EdgeEffectCompat(context);
				mEdgeGlowLeft = new EdgeEffectCompat(context);
				mEdgeGlowRight = new EdgeEffectCompat(context);
			}
		} else {
			mEdgeGlowTop = null;
			mEdgeGlowBottom = null;
			mEdgeGlowLeft = null;
			mEdgeGlowRight = null;
		}
	}

	@Override
	public void dispatchDraw(Canvas canvas) {
		super.dispatchDraw(canvas);
		if (mEdgeGlowTop != null) {
			final int scrollX = getScrollX();
			final int scrollY = getScrollY();
			if (!mEdgeGlowTop.isFinished()) {
				final int restoreCount = canvas.save();
				final int width = getWidth() - getPaddingLeft() - getPaddingRight();

				canvas.translate(getPaddingLeft() + scrollX, Math.min(0, scrollY));
				mEdgeGlowTop.setSize(width, getHeight());
				if (mEdgeGlowTop.draw(canvas)) {
					ViewCompat.postInvalidateOnAnimation(this);
				}
				canvas.restoreToCount(restoreCount);
			}
			if (!mEdgeGlowBottom.isFinished()) {
				final int restoreCount = canvas.save();
				final int width = getWidth() - getPaddingLeft() - getPaddingRight();
				final int height = getHeight();

				canvas.translate(-width + getPaddingLeft() + scrollX,
						Math.max(getScrollRangeY(), scrollY) + height);
				canvas.rotate(180, width, 0);
				mEdgeGlowBottom.setSize(width, height);
				if (mEdgeGlowBottom.draw(canvas)) {
					ViewCompat.postInvalidateOnAnimation(this);
				}
				canvas.restoreToCount(restoreCount);
			}
			if (!mEdgeGlowLeft.isFinished()) {

				final int restoreCount = canvas.save();
				final int width = getWidth();
				final int height = getHeight() - getPaddingTop() - getPaddingBottom();

				canvas.rotate(270);

				canvas.translate(-height + getPaddingTop() - scrollY, Math.min(0, scrollX));
//                canvas.rotate(90, 0, 0);
				mEdgeGlowLeft.setSize(height, width);
				if (mEdgeGlowLeft.draw(canvas)) {
					ViewCompat.postInvalidateOnAnimation(this);
				}
				canvas.restoreToCount(restoreCount);
			}
			if (!mEdgeGlowRight.isFinished()) {
				final int restoreCount = canvas.save();
				final int width = getWidth();
				final int height = getHeight() - getPaddingTop() - getPaddingBottom();

				canvas.rotate(90);
				canvas.translate(-getPaddingTop() + scrollY,
						-(Math.max(getScrollRangeX(), scrollX) + width));
				mEdgeGlowRight.setSize(height, width);
				if (mEdgeGlowRight.draw(canvas)) {
					ViewCompat.postInvalidateOnAnimation(this);
				}
				canvas.restoreToCount(restoreCount);
			}
		}
	}

	private static int clamp(int n, int my, int child) {
		if (my >= child || n < 0) {
            /* my >= child is this case:
             *                    |--------------- me ---------------|
             *     |------ child ------|
             * or
             *     |--------------- me ---------------|
             *            |------ child ------|
             * or
             *     |--------------- me ---------------|
             *                                  |------ child ------|
             *
             * n < 0 is this case:
             *     |------ me ------|
             *                    |-------- child --------|
             *     |-- mScrollX --|
             */
			return 0;
		}
		if ((my + n) > child) {
            /* this case:
             *                    |------ me ------|
             *     |------ child ------|
             *     |-- mScrollX --|
             */
			return child - my;
		}
		return n;
	}

	@Override
	protected void onRestoreInstanceState(Parcelable state) {
		if (!(state instanceof SavedState)) {
			super.onRestoreInstanceState(state);
			return;
		}

		SavedState ss = (SavedState) state;
		super.onRestoreInstanceState(ss.getSuperState());
		mSavedState = ss;
		requestLayout();
	}

	@Override
	protected Parcelable onSaveInstanceState() {
		Parcelable superState = super.onSaveInstanceState();
		SavedState ss = new SavedState(superState);
		ss.scrollYPosition = getScrollY();
		ss.scrollXPosition = getScrollX();
		return ss;
	}

	static class SavedState extends BaseSavedState {
		public int scrollYPosition;
		public int scrollXPosition;

		SavedState(Parcelable superState) {
			super(superState);
		}

		public SavedState(Parcel source) {
			super(source);
			scrollYPosition = source.readInt();
			scrollXPosition = source.readInt();
		}

		@Override
		public void writeToParcel(Parcel dest, int flags) {
			super.writeToParcel(dest, flags);
			dest.writeInt(scrollYPosition);
			dest.writeInt(scrollXPosition);
		}

		@Override
		public String toString() {
			return "HorizontalScrollView.SavedState{"
					+ Integer.toHexString(System.identityHashCode(this))
					+ " scrollXPosition=" + scrollXPosition + " scrollYPosition=" + scrollYPosition + "}";
		}

		public static final Creator<SavedState> CREATOR
				= new Creator<SavedState>() {
			public SavedState createFromParcel(Parcel in) {
				return new SavedState(in);
			}

			public SavedState[] newArray(int size) {
				return new SavedState[size];
			}
		};
	}

	static class AccessibilityDelegate extends AccessibilityDelegateCompat {
		@Override
		public boolean performAccessibilityAction(View host, int action, Bundle arguments) {
			if (super.performAccessibilityAction(host, action, arguments)) {
				return true;
			}
			final HVScrollView nsvHost = (HVScrollView) host;
			if (!nsvHost.isEnabled()) {
				return false;
			}
			switch (action) {
				case AccessibilityNodeInfoCompat.ACTION_SCROLL_FORWARD: {
					final int viewportHeight = nsvHost.getHeight() - nsvHost.getPaddingBottom()
							- nsvHost.getPaddingTop();
					final int viewportWidth = nsvHost.getWidth() - nsvHost.getPaddingRight()
							- nsvHost.getPaddingLeft();
					final int targetScrollY = Math.min(nsvHost.getScrollY() + viewportHeight,
							nsvHost.getScrollRangeY());
					final int targetScrollX = Math.min(nsvHost.getScrollX() + viewportWidth,
							nsvHost.getScrollRangeX());
					if (targetScrollY != nsvHost.getScrollY() || targetScrollX != nsvHost.getScrollX()) {
						nsvHost.smoothScrollTo(targetScrollX, targetScrollY);
						return true;
					}
				}
				return false;
				case AccessibilityNodeInfoCompat.ACTION_SCROLL_BACKWARD: {
					final int viewportHeight = nsvHost.getHeight() - nsvHost.getPaddingBottom()
							- nsvHost.getPaddingTop();
					final int viewportWidth = nsvHost.getWidth() - nsvHost.getPaddingRight()
							- nsvHost.getPaddingLeft();
					final int targetScrollY = Math.max(nsvHost.getScrollY() - viewportHeight, 0);
					final int targetScrollX = Math.min(nsvHost.getScrollX() - viewportWidth, 0);
					if (targetScrollY != nsvHost.getScrollY() || targetScrollX != nsvHost.getScrollX()) {
						nsvHost.smoothScrollTo(targetScrollX, targetScrollY);
						return true;
					}
				}
				return false;
			}
			return false;
		}

		@Override
		public void onInitializeAccessibilityNodeInfo(View host, AccessibilityNodeInfoCompat info) {
			super.onInitializeAccessibilityNodeInfo(host, info);
			final HVScrollView nsvHost = (HVScrollView) host;
			info.setClassName(ScrollView.class.getName());
			if (nsvHost.isEnabled()) {
				final int scrollRangeY = nsvHost.getScrollRangeY();
				final int scrollRangeX = nsvHost.getScrollRangeX();
				if (scrollRangeY > 0 || scrollRangeX > 0) {
					info.setScrollable(true);
					if (nsvHost.getScrollY() > 0 || nsvHost.getScrollX() > 0) {
						info.addAction(AccessibilityNodeInfoCompat.ACTION_SCROLL_BACKWARD);
					}
					if (nsvHost.getScrollY() < scrollRangeY || nsvHost.getScrollX() < scrollRangeX) {
						info.addAction(AccessibilityNodeInfoCompat.ACTION_SCROLL_FORWARD);
					}
				}
			}
		}

		@Override
		public void onInitializeAccessibilityEvent(View host, AccessibilityEvent event) {
			super.onInitializeAccessibilityEvent(host, event);
			final HVScrollView nsvHost = (HVScrollView) host;
			event.setClassName(ScrollView.class.getName());
			final AccessibilityRecordCompat record = AccessibilityEventCompat.asRecord(event);
			final boolean scrollableX = nsvHost.getScrollRangeY() > 0;
			final boolean scrollableY = nsvHost.getScrollRangeX() > 0;
			boolean scrollable = scrollableX || scrollableY;
			record.setScrollable(scrollable);
			record.setScrollX(nsvHost.getScrollX());
			record.setScrollY(nsvHost.getScrollY());
			record.setMaxScrollX(nsvHost.getScrollRangeX());
			record.setMaxScrollY(nsvHost.getScrollRangeY());
		}
	}


	public void setFillViewportH(boolean fillViewportH) {
		if (mFillViewportH != fillViewportH) {
			this.mFillViewportH = fillViewportH;
			requestLayout();
		}
	}

	public void setFillViewportV(boolean fillViewportV) {
		if (mFillViewportV != fillViewportV) {
			this.mFillViewportV = fillViewportV;
			requestLayout();
		}
	}

	public void setFillViewportHV(boolean fillViewportH, boolean fillViewportV) {
		if (mFillViewportH != fillViewportH || mFillViewportV != fillViewportV) {
			this.mFillViewportH = fillViewportH;
			this.mFillViewportV = fillViewportV;
			requestLayout();
		}
	}

	@Override
	public boolean canScrollHorizontally(int direction) {
		if (direction > 0) {
			return getScrollX() < getScrollRangeX();
		} else {
			return getScrollX() > 0 && getScrollRangeX() > 0;
		}
	}

	@Override
	public boolean canScrollVertically(int direction) {
		if (direction > 0) {
			return getScrollY() < getScrollRangeY();
		} else {
			return getScrollY() > 0 && getScrollRangeY() > 0;
		}
	}
}